OP-Z and Access Virus Classic

I bought an old Access Virus Classic to go with my Op-z because of its mega miltitimbrality. I can use all tracks from OP-Z with completely different sounds from only one amazing machine! But have run into some problems, and dont know if it is the Virus that have trouble, or if its the OP-Z that dont go well with this old synth.

All midi works fine until I change a pattern. Then the Virus stops responding and I have to change to multimode and back singlemode to make it work again.
When I do this a couple of times, the sound becomes very low and I have turn the Virus off/on to make it normal again.

Does anyone know why this might be? Is it the Virus that has problems, or is it the OP-Z that is the problem.

I have sold all my other sequencers so I have no way to check if the Virus gets the same problems with other machines. Can anyone help me?

It seems to be a problem only in some previous made projects. If I start from scratch in a new project, I can change patterns as much as I like, and there are no problems.

Still, if anyone know what the problem might be, please let me know.

I think it’s because settings are stored per pattern. That’s why it works fine when you start fresh.

Thank you! That seems to be it! I set all CCs on OPZ to zero, and now there is no problems :slight_smile:

Just wondering, you said that you set all of the MIDI cc’s to 0. Are you referring to the MIDI CC# or the value of the parameter being 0?
Does this mean you are not using the OP-Z to control parameters on the Virus? Or are you saying that you need to set the value of each mapped MIDI CC parameter on the OP-Z to zero for it to work without bugs?

Be aware that the OP-Z can send MIDI program changes when you switch projects and patterns on the OP-Z. If the Virus is listening for program changes, then changing a pattern on the OP-Z can change the patch on the Virus. There are two ways to configure the program change behavior on the OP-Z, you can choose to use MIDI channels 1-10 or MIDI channels 1 and 2 for sending and receiving program change messages. If I were you, I would first try to disable program change receive on the Virus (if possible) and try changing projects and patterns on the OP-Z to see if this prevents your patches from changing unpredictably on the Virus to rule out if it’s program change messages that are causing the unexpected behavior.

Thank you for your input! My problem was that some midi CC from op-z interfered with the Virus. I read somewhere that CC# 7 controls volume on the Virus. This is sustain on the op-z synth tracks, so it was probably a plucky sound that lowered the volum on Virus.

I dont use the op-z midi CCs to control Virus because I want the sounds from op-z also, as layering, with different ADSR, delays, tapeeffects, etc.

How do you choose which midi channel op-z sends program change on?

Shift + 7 is the shortcut to change the MIDI program change mode / MIDI channels it uses for this - it’s mentioned in the manual at the following link:

Thank you! I did not catch this update in the manual :slight_smile:

No, sorry, Im still confused about midi program change. In the app I dont see “Enable program change”, the shift+6 function. Only “Alt program change”, the shift+7 function. Is this normal? Maybe that could be part of my program change problem? My Virus dont respond to program change from OP-Z, neither has any other synth (A4 and Digitakt) I have connected it to.